Railway-traffic-controlling apparatus



R. A. M CANN RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Feb. 14. 1924 Fly". 5.

Patented Get. 21, 1924.

UNITED STATES PATENT OFFICE.

RONALD MCCANN, F SWISSVALE, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNAL COMPANY, 01? SWISSVALE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

RAILWAY-TRAFFIC-CONTROLLING APPARATUS.

Application filed February 14, 1924. Serial No. 692,682.

T 0 all whom it may concern:

Be it known that I, RONALD A. MQCANN,

a citizen of the United States, residing at Swissvale, in the county of Allegheny and State of Pennsylvania, have invented certion new and useful Improvements in Railway-Traflic-Controlling Apparatus, of which the following is a specification.

My invention relates to railway traffic 1 controlling apparatus and particularly to apparatus of the type wherein governing means on a train are controlled by alternating currents which are supplied to the track rails in accordance with traflic conditions in advance of the train. More specifically my invention relates to apparatus of this type wherein the alternating train governing currents in the track rails are superposed upon direct current track circuits including storage batteries, and wherein rectifying devices supplied from the source of alternating current are provided for the purpose of charging such storage batteries.

One feature of my invention is the provision in apparatus of the type described of means for preventing false indications on a train due to periodic current applied to the track rails by such rectifiers.

In the accompanying drawing, Fig. 1 is a diagrammatic view showing one form and arrangement of trackway apparatus embodying my invention. Figs. 2 and 3 are views showing modifications of the apparatus illustrated in Fig. 1 and also embodying my invention. 1

Similar reference characters refer to similer parts in all three views.

Referring first to Fig. 1, the reference characters 1 and 1 designate the track rails of a railroad over which traffic normally moves in the direction of the arrow. These rails are divided, by means of insulated joints 2, into a plurality of successive track sections of which only one section A-B is shown in the drawing.

Located at point B is a trackway signal S of any suitable form. As here shown signal S is a semaphore signal capable of displaying a proceed, a caution, or a stop indication, controlled in any suitable manner in accordance with traffic conditions in advance.

The reference character T designates a track transformer having a secondary winding 4 connected across the rails adjacent the right hand end of section AB. Interposed between winding 4 and one rail 1 of section AB isa track circuit storage battery 3 for the control of a direct current track relay B. When signal S is at proceed or caution alternating current is supplied to primary 5 of transformer T from secondary 11 of transformer H over circuit controller 10 operated by signal S. The primary 12 of transformer H is constantly supplied with alternating current from some suitable source not shown in the drawing. It is therefore clear that section AB is constantly supplied with direct current, and is also supplied with alternating train governing current when signal S is at proceed or caution.

Battery B is arranged to be charged by a suitable form of rectifier from the alternating current source. As here shown the charger G is a mechanical rectifier of the usual form and comprises a transformer U having its primary winding 6 connected in parallel with primary 5 of track transformer T. A polarized armature 7 is arranged to respond to reversals in the relative polarity of the current in the primary 6 of transformer U, to connect the right hand side of battery B alternately with the right hand and left hand terminals of the secondary of transformer U. To accomplish this result two fixed contacts 8 and 9 co-operate with armature 7 and are connected with the free ends of windings 6 and 6 respectively. The common terminal of windings 6 and 6 is constantly connected with the left hand side of battery 8. The rectifier therefore operates as a trickle charger to supply uni-directional current to battery 3.

The trackway apparatus here shown is suitable for co-operation with train carried groverning mechanism so that when the train occupies a portion of track which is being supplied with train governing current the train receives a proceed indication, and when the train occupies a stretch of track to which the supply of such current is interrupted, the train receives a stop indication. In at least one form of apparatus arranged to operate in this manner the train carried mechanism is controlled by the train governing current in the rails through the medium of a pick-up coil in inductive relation with the rails. I

As shown in the drawing, signal S is at proceed and train governing current is therefore supplied to the rails of section AB and a train proceeding through this section would therefore receive a proceed indication v If signal S were at stop the supply of train governing current wouldbe interrupted and the train would then receive a stop indication. Y

- It should be pointed out that with apparatus of this type a portion of the pulsating, uni-directional current supplied by charger G will flow in the track rails, and this current might cause a proceed indication to. be received on the train in the same manner as. the train governing current. In my invention therefore, to prevent the train fromreceiving a false proceed indication when the signal in advance is at-stop, I arrange such time to discontinue the supply of energy to transformer U.

111 the modification shown in Fig. 2, section AB is provided with apparatus similar to that shown in Fig. 1 and in addition -a relay R is connected across the rails ad acent the left hand end of section AB. Section JA is provided adjacent its right handend-withapparatus for supplying the rails with alternating and direct current which apparatus is. the same as already explained in connection with the apparatus for section A-B, except that energy is sup plied to primary 5 of transformer T and the primary 6 of transformer U from a transformer H" similar to transformer H, over a front contact of relay R instead of circuit controller 10. It follows that direct current. is. constantly supplied to the rails of both sections and that alternating current is supplied to the rails of section AB, as before, only when signal S indicates proceed or caution. It will also be clear that. section J.A is supplied with alternating current only when relay R is energiized. In Fig. 2, the chargers G and G are each disconnected from their energy. source when the associated. train governing transformer is ole-energized.

Referring. now to Fig/3, in this modification the apparatus is the same as shown in Fig.2, except that transformers T, U, '1" and U= are all supplied with energy from transformer H. It will be clear from the drawing that. transformers U and T are energized. when signal S: indicates proceed or caution whereas transformers U and T are energized when, signal S indicates proceed or, caution and relay R is energized. The

operation of the apparatus will be obvious without further explanation. I

. 'ii lthough I have herein shown and de scribed. only a. few-forms of railway traffic controlling apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. Railway trafic controlling apparatus comprising a stretch of railway track, a

track battery connected with the rails of said stretch, a rectifier for charging said battery, and'ineans responsive to traflic conditions for controlling said rectifier. I

2. Railway traffic controlling apparatus comprising a stretch of railway track, a battery connected with the rails of said stretch, a source of alternating current, a rectifier interposed between saidbattery and said source, and means controlled by traffic conditions for. at times disconnecting said source from said rectif er.

3. In combination, a stretch of railway track, means for. supplying said stretch with alternating train governing current, a battery connected with the rails of the stretch, a source of alternatin current, a rectifier for charging said-battery from said source, and means for controlling said first means and the supply of' current to said rectifier in accordance with traiiic conditions.

4'. In combination, a stretch of railway track, a transforiner. havinga secondary connected with the rails of the stretch, a bat tery also connected with said rails,.a rectitier for charging said battery, and means under the control of trafiic conditions for at 7 times supplying alternating current to saidrectifier and to the primary of said transformer. r i

5. In combination, a stretch of railway track, a transformerhaving a first winding connected with the "rails of the stretclnwa battery. also connected with. said rails, a rectifier for charging. said battery, a trackway signal responsive. to traffic conditions, and

means controlled by said signal for at times current to said rectifier and to a second windingof said transformer.

7. In combination, a stretch of railway track, a track transformer having a wind ingconnected across the rails ofthe' stretch, a battery interposed between said winding and one rail of the stretch, aTectrfie-r for charging said battery, a source of alternating current, and means responsive to traffic conditions in advance of the stretch for at times connecting said source with asecond winding on said transformer and with said rectifier.

8. In combination, a stretch of railway track, a track transformer having a winding connected across the rails of the stretch, a battery interposed between said winding and one rail ofthe stretch, a rectifier for charging said battery, a source of alternating current, means for at times connecting said source with a second winding on said transformer and with said rectifier so that when said second winding is disconnected from said source the flow of periodic current from said source to, the rails through the rectifier is prevented.

9. In combination, a stretch of railway track, a track transformer having a winding connected across the rails of said stretch, a battery in series with said winding, an amp iliary transformer having a secondary connected with said battery, a rectifier interposed between said auxiliary transformer and said battery, and means responsive to traffic conditions in advance of said stretch for at times supplying alternatingcurrent to the primary winding of said track transformer and to the primary winding of said auxiliary transformer in parallel.

10. In combination, stretch of railway track divided into a forward section and a rear section, a track transformer having a winding connected across the rails of said forward section, a first battery connected in series with said winding, means responsive to traflic conditions in advance of said for ward section for at times supplying alternating current to a second winding on said transformer connected in parallel with said second winding, a relay responsive to cur rent from said battery, a second battery connected with said rear section, charging means for said second battery, and means controlled by said relay for supplying energy to said last charging means.

11. In combination, a stretch of railway track divided into a forward section and a rear section, a track transformer having a winding connected across the rails of said forward section, a first battery connected in series with said winding, a first rectifier for charging said battery, means controlled by trafiic conditions in advance of said forward section for at times supplying said winding and said rectifier with alternating current, a second battery connected across the rails of said rear section, a second rectifier for charging said battery, and means responsive to traffic conditions in said forward section and in advance of said f rward section for at times supplying alternating current to said second rectifier.

12. In combination, a section of railway RONALD A. MoCANN. 

